1. Field of the Invention
The present invention relates to electrical connector systems. More specifically, the present invention relates to electrical connector systems that exhibit low cross-talk.
2. Brief Description of Earlier Developments
Consumer demand for higher speed electronic devices affects all of the components used in an electronic device. As an example, the electrical connectors used in these electronic devices must be designed so as to ensure that the connectors will operate at these increased speeds without, for example, affecting signal integrity or interfering with any nearby components. In addition to the demand for increased operating speed, the design of the electronic device typically requires that the electrical connector occupy the same, if not less, area within the device.
One concern with operating electrical connectors at high speeds (e.g. approximately 100 MHz and above) is controlling cross-talk. Cross-talk occurs when electromagnetic energy transmitted through a conductor in the connector causes electrical currents in the another conductor in the electrical connector. Near-end cross-talk (NEXT) travels in a direction opposite to the signal in the conductor. As an example, ANSI/EIA/TIA/568A Category 5 requirements limit pair-to-pair NEXT to xe2x88x9240 dB at 100 MHz. Some applications require such cross-talk performance, but measured on a power sum basis.
Various techniques currently exist to improve cross-talk performance in an electrical connector system. Some techniques reduce the amount of cross-talk created by the system (hereinafter called unwanted cross-talk). For instance, U.S. Pat. No. 5,571,035 describes an insert placed within a modular jack plug housing. The insert locates the conductors of each pair close to each other, while separating the pair from other pairs to reduce the amount of cross-talk generated by the system. At the location of the insert, the conductor wires are no longer arranged as twisted pairs.
Other techniques deliberately introduce a cross-talk to the system (hereinafter compensating cross-talk) that reduces, or offsets, any unwanted cross-talk generated by the system. As an example, U.S. Pat. No. 5,562,479 describes an insert placed within a cable connector housing. The insert aligns the wires in a side-by-side orientation to create the compensating cross-talk.
U.S. Pat. No. 5,921,818 describes a modular jack receptacle using insulation displacement contacts on lead frames. Selected conductors crossover each other within the receptacle housing.
British Patent Application GB 2 314 466 describes a compensation pattern on a multi-layer board (MLB) to which contacts from an electrical connector secure. Capacitive coupling between adjacent unlike paths produces a compensating cross-talk to reduce the unwanted cross-talk produced by the connector. The pattern also staggers adjacent paths on a layer in order to allow coupling between non-adjacent paths.
European Patent Application number EP 0 854 664 also describes a compensation pattern on an MLB to which the electrical connector contacts connect. The arrangement of the paths ensures that one path of a pair overlies at least two paths, each from a different pair.
While these techniques can help reduce, or even prevent, cross-talk, further increases in the operating speeds of electronic devices continually demand additional measures for cross-talk prevention or cross-talk prevention.
It is an object of the present invention to provide an electrical connector system with features for cross-talk compensation.
It is a further object of the present invention to provide a low cross-talk electrical connector system.
It is a further object of the present invention to provide an apparatus for reducing cross-talk capable of being used with current electrical connectors.
It is a further object of the present invention to provide an apparatus for reducing cross-talk that does not require extensive redesign of current electrical connector systems.
These and other objects of the present invention are achieved in one aspect of the present invention by an electrical connector system, comprising: an electrical connector; a plurality of wires extending from the connector and arranged in a twisted pair; and an insert separating the wires defining each of the twisted pairs.
These and other objects of the present invention are achieved in another aspect of the present invention by a method of reducing crosstalk in an electrical connector system that produces an unwanted crosstalk, comprising the steps of: providing an electrical connector with a plurality of wires extending therefrom and arranged in a plurality of twisted pairs; providing an insert; placing the insert between the wires defining each of said twisted pairs. The insert causes the wires to produce a compensating cross-talk that offsets the unwanted cross-talk.
These and other objects of the present invention are achieved in another aspect of the present invention by an electrical connector system having an electrical connector with at least two twisted pairs of wires extending therefrom, wherein the improvement comprises an insert placed between the wires defining each of the twisted pairs.
These and other objects of the present invention are achieved in another aspect of the present invention by a method of using an electrical connector that exhibits an acceptable level of cross-talk within a desired frequency range, comprising the steps of: providing an electrical connector system that is unable to exhibit the acceptable level of cross-talk within the desired frequency range, the system including: an electrical connector; and a plurality of wires extending from the connector and arranged in a plurality of twisted pairs; separating the wires defining each of the twisted pairs; and operating the connector system within the desired frequency range. As a result, the connector system exhibits the desired level of cross-talk.